DEC Issues Proposal For Lake

Chemical Additives Required For Three Treatment Plants

November 22, 2012

The state Department of Environmental Conservation submitted its proposal for limiting the amount of phosphorus discharged into Chautauqua Lake to the U.S. Environmental Protection Agency.

The proposed limits to foster compliance with water quality standards, known as a total maximum daily load, are required under the federal Clean Water Act.

"Chautauqua Lake is a Western New York treasure that in recent years had beach closures due to algae blooms triggered by excessive phosphorus in the lake," said Joe Martens, DEC commissioner. "This summer was a particularly bad one for the lake, with beach closures and numerous complaints of algal blooms, including toxic blue-green blooms. This TMDL provides a specific program to improve the lake's water quality."

Since 2004, the DEC has identified Chautauqua Lake as a water body not meeting water quality standards and needing a total maximum daily load statement to bring it into compliance. DEC officials prepared the total maximum daily load and submitted it to EPA for its approval. The EPA has 30 days to approve or modify the TMDL.

A total maximum daily load specifies the maximum amount of a pollutant that a water body can receive and still meet water quality standards. Total maximum daily loads account for all contributing sources which include point sources such as wastewater treatment plants and nonpoint sources such as agricultural runoff, and natural background levels. The total maximum daily load also account for seasonal variations in the pollutant load and incorporates a margin of safety that considers unknown or unexpected sources of the pollutant.

The federal Clean Water Act requires states to develop total maximum daily loads for waterbodies identified as not meeting water quality standards. The process allocates required reductions in pollutant loadings to specific sources to bring waters into compliance. Under the Clean Water Act, states are required to submit proposed total maximum daily loads to the EPA for approval.

Among other actions, the total maximum daily load requires the three largest wastewater treatment plants serving the Chautauqua Heights Sewer District, North Chautauqua Lake Sewer District and Chautauqua Utility District, all in the town of Chautauqua, to implement relatively low-cost chemical addition to remove phosphorus by next summer. More significant treatment upgrades would be required by 2018.